Mere thoughts about matters of belief are not Waswasah
8-3-2014 | IslamWeb
Question:
As-salamu 3laikum, In one fatwa you said that doubts which merely cross the mind are just waswaas, whereas doubts that settle in the heart are kufr. I have a problem with this that I am worried about and I asked this question before but I could not find the answer in the fataawa you sent me to. My problem is that sometimes the shaytaan whispers something to me and I know it is wrong but then I try to think of the evidence from the Qur'an and sunnah to confirm that it was wrong otherwise the whispers don't go away. Is this ok? The second problem is that sometimes a question comes to my mind and I am not sure about it so I try to think of the right answer and then I realise that it was an obvious matter of belief. But the question was about an implication of the belief not the belief itself so for some reason, either I forgot or I did not realize the implication or I could not reason properly for a few seconds. Does this count as crossing the mind or settling in the heart? It is not the same as whispers that you instantly know are wrong but I am not deliberately doubting anything just that sometimes understanding how a question relates to an issue of aqueedah is not clear to me. But afterwards when I think about it it does become clear and I feel terrible that I could not come to the right conclusion instantly. Jazaakumu Allahu khairan
Answer:
All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad 
is His slave and Messenger.
As we have already stated to you in our previous Fataawa 87166, 88597 and 91084, certainty is not removed by doubt; this is an important rule that a Muslim needs in many religious matters. So, if the belief is firm in the heart, then the doubts that someone may have are not harmful, even if they were related to the basic principles of faith. All that is required of a Muslim is to repel those doubts. We hope that you have understood this meaning from our previous Fataawa. This is the most important matter.
On the other hand, referring to the Quran and the Sunnah in order to confirm that a certain thought was wrong is something good, and there is nothing wrong with mere thinking about a matter that comes to your mind; but you should beware of this becoming a devilish whisper that would lead to unpleasant consequences, or wasting your time instead of being preoccupied with what benefits you.
Allaah knows best.